Unsupported platinum nanoparticles as effective sensors of neurotransmitters and possible drug curriers

Abstract

Herein, surface-enhanced Raman scattering (SERS) activity of positively charged unsupported platinum nanoparticles (PtNPs) with ∼12nm size and narrow size distribution, in an aqueous solution, towards neurotransmitters was monitored at 785nm excitation wavelength. The pure PtNPs were synthetized by polyol method. Their morphology and structure were checked by scanning electron microscopy (SEM) and X-ray diffraction spectroscopy (XRD) measurements. As a neurotransmitter bombesin (BN), which exhibits autocrine effect on the growth of normal and tumour tissues, and its fragments from the C-terminal end: BN13−14, BN12−14, BN11−14, BN10−14, BN9−14, and BN8−14 (X-14 fragments of the BN amino acid sequence) were chosen. The collected spectra were interpreted and discussed. This is to determine the adsorption mode of bombesin onto the PtNPs surface and changes in this mode as a result of the bombesin backbone shortening from the N-terminal end. This is important from the point of using PtNPs as potential BN carrier into the cancerous tissue and antitumor drug.